package java1224;

public class Java01 {
    public static void main(String[] args) {
        //变量和常量
        //变量的值就是可以更改的
        int a = 2;
        System.out.println(a);
        a =3;
        a =5;
        a =7;
        System.out.println(a);

        //常量 就是不能更改的  关键字 final
        final  int b = 6;

        //数字类型
        int salary = 1_000_000_000;
        double d = 3.141592_65358_979;
        System.out.println(d);
        System.out.println(salary);

        //赋值运算符
        int x  =3;
        double y =3.0;
        x +=y;
        System.out.println(x);


    }
}
